Journal ArticleDOI
The N-Alkylation and N-Arylation of Unsymmetrical Pyrazoles
Grimmett,Khr Lim,RT Weavers +2 more
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TLDR
In this article, the ratios of the isomeric N-methyl pyrazoles have been determined by N.M.R. and g.l.c. analysis, and explanations for the observed product orientations involve considerations of electronic and steric effects, the possible intermediacy of quaternary salts, and the likelihood that the dominant tautomer is reacting.Abstract:
Unsymmetrical pyrazoles with alkyl, aryl, nitro and carboxyl substituents at C3 or C5 have been methylated with dimethyl sulfate in methanol, dimethyl sulfate in basic medium, and with diazomethane. The ratios of the isomeric N-methylpyrazoles have been determined by N.M.R. and g.l.c. analysis. The modified Ullmann phenylation has also been applied to these pyrazoles. Explanations for the observed product orientations involve considerations of electronic and steric effects, the possible intermediacy of quaternary salts, and, in some instances, the likelihood that the dominant tautomer is reacting.read more
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Journal ArticleDOI
Palladium-catalyzed coupling of lactams with bromobenzenes
TL;DR: In this article, an efficient method for the coupling of lactams with bromobenzenes mediated by palladium acetate and DPPF is presented, and the reaction proceeds efficiently with a variety of lactam and both electron-rich and poor substituted bromogenes.
Journal ArticleDOI
The scope and limitations of deuteration mediated by Crabtree's catalyst
TL;DR: The electronic effects of substituents in the arene ring are critical only where the directing group is poor, in which case exchange is generally promoted by electron donating substitusents, but the exchange is impeded by bulky meta-substituents as discussed by the authors.
Journal ArticleDOI
Discovery of a novel glucagon receptor antagonist N-[(4-{(1S)-1-[3-(3, 5-dichlorophenyl)-5-(6-methoxynaphthalen-2-yl)-1H-pyrazol-1-yl]ethyl}phenyl)carbonyl]-β-alanine (MK-0893) for the treatment of type II diabetes.
Yusheng Xiong,Guo Jian,Mari R. Candelore,Rui Liang,Corey Miller,Qing Dallas-Yang,Guoqiang Jiang,Peggy E. McCann,Sajjad A. Qureshi,Xinchun Tong,Shiyao Sherrie Xu,Jackie Shang,Stella H. Vincent,Laurie Tota,Michael Wright,Xiaodong Yang,Bei B. Zhang,James R. Tata,Emma R. Parmee +18 more
TL;DR: Compound 9m blunted glucagon-induced glucose elevation in hGCGR mice and rhesus monkeys and lowered ambient glucose levels in both acute and chronic mouse models.
Journal ArticleDOI
Mild Palladium-Catalyzed Regioselective Direct Arylation of Azoles Promoted by Tetrabutylammonium Acetate
Journal ArticleDOI
An efficient solvent-free synthesis of NH-pyrazoles from β-dimethylaminovinylketones and hydrazine on grinding
Kelvis Longhi,Dayse N. Moreira,Mara R. B. Marzari,Vagner M. Floss,Helio G. Bonacorso,Nilo Zanatta,Marcos A. P. Martins +6 more
TL;DR: A series of NH-pyrazoles was efficiently synthesized from the reaction of b-dimethylaminovinylketones ([R 1 C(O)C(R 2 )@CHN(Me2)], where R
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